John walker



(No Modl.)

A l J. WALKER, y,

DBPH-QSPHORIZING ANDOTHERWISEPURIIFYINGv MOLTBN IRON 0R STEEL'.

No. 244,696. Patented July 19,1881.l Y

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-i UNITED STATESA PATENT OFFICE.

JOHN wALxEE, OE CLEVELAND, OHIO, AssIeNoE To HIMsELE AND wILsON B. oHIsHoLM, OE sAME PLAGE.

DEPHOSPHORIZING AND OTHERWISE PURIFYING MOLTEN IRON R STEEL.

SPECIFICATION' formingpart of Letters VPatent No. 244,696, dated July.19, l8 81.

Application filed March 24,1881. (No model.)

To all whom 1it may concern Be it known that I, JOHN WALKER, of Cleveland, county of Cuyahoga, State of Ohio, have invented or discovered a new and useful Im- 5 provement in Dephosphorizing and otherwise Purifying Molten Iron or Steel 5 and I do hereby declare the following. to be a full, clear, concise, and exact description thereof, reference being had to the accompanying drawings, mak- Io ing a part of this specification, in which-like letters indicating like parts- Figure lis a vertical sectional view of a box charged with suitable material for dephosphorizing purposes, and illustrative'of my present invention, and Fig. 2 is a horizontal sectional view' thereof in the plane of the line x w, Fig. 1. The fact that various materials, such as alumina, magnesia, Src., are useful elements in the elimination of phosphorus and other impurities in the making of iron, is well known in the art, and in connection with the Bessemer and Siemens-Martin Vor open-hearth processes, such ingredients have been utilized for such purposes by workin g them into the linings of-the converter or hearth, as in the basiclining process,77 so called. In the use of such or other like purifying agents it is sometimes important that they be so applied that the entire body or mass of the molten metal shall be subject to their action. It is well known that the metal, both in the Bessemer and open-l hearth processes, is necessarily at a high temperature, so that even if an amount of dephosphorizin g material chemicallysufcient be introduced at a single charge it is liable to be fused or gasified, or to go into other combinations, and its dephosphorizing action exhausted before the entire body or mass of the molten metal has been subjected to its action.

By my present invention I inclose the dephosphorizing or other purifying agents ina box or case composed of a series of two or more chambers, preferably one inside the other, in such manner that the inclosing-walls of the several chambers shall be successively fused at dilferent times, one after another, and thereby different portions of the entire charge shall successively be brought into contact or intermixture with the molten metal,wherebythe process of dephosphorization and elimination of j in gredieuts are placed.

l Assuml other impurities sh all be carried on more slowly and under such conditions that all, or substantially all, parts of the molten metal shall be subjected tothe action of the ingredients so introduced. y

'Ihe box vor case A may bemade of any snitable material, but for most purposes I prefer cast-iron, both on accountof cheapness and because such material may be added to the charge without injury, and sometimes with positive benefit to the product. It may be made of any desired size and proportions; and while I have found that a diameter and height ot' one foot, with other parts, as shown, proportioned to about the same scale, gives good results, I do not limit myself thereto.

As shown, the box or case consists of a bottom, a, a cylindrical outer side, a', and two concentric inner rings, a2 a3, spaced and shaped so as to give a series of chambers, b b 112,'into which the dephosphorizing or other purifying A lid or cover, a4, is

then cast on top of the case insuch mannersay by bevels, as shown, or otherwise-'as to be retained or kept firmly in place. This cover may, however, be made of other material, if so preferred.

'ng the dephosphorizin g process to be employed, andthe several chambers b b' b2 to contain sufficient dephosphorizin g material for treating one entirey charge of molten metal, the box or case is then at the proper time placed "direotly into the molten mass. The intense ','hea't will fuse ir'st the outer sll'ell, and then 1 the contents of the outer chamber will unite or iutermix with the charge, and by the usual "chemical action dephosphorize it in part.

At or about the time, as near as may be, that this part of the charge has exhausted its dephosphorizing capacity the next inner shell will be fused, and the contents of chamber b will come in contact or be intermixed with the molten mass, so that the dephosphorizing operation will still go on.

In the Bessemer process the violent agitation caused by blowing will so intermix the metal and thel dephosphorizing ingredients thus successively broughtinto action that practically the entire charge will have been subjected to the chemical action indicated by the time the contents of the innermost chamber, b2, shall have exhausted their action; and in the openhearth process, if the agitation of the metal is not sutcient for this purpose, mechanical means, such as are well known in the art, may be resorted to in order to attain the desired result. Any material suitable for the purpose may be used in the chambers b b b2, such as magnesian limestone having a considerable percentage of magnesia-say thirty to forty per centum, more or less-with or without the alumina.

If limestone having the requisite percentage of magnesia is not obtainable, an artificial compound may be used; but as regards material, I do not limit myself to any particular mixture or natural product, provided only it be suitable for the purpose.

If the charge be so large, or the capacity of the case employed be so small that the contents of one case will be insufficient to complete the work desired, two or more cases may be employed, one being pnt in first and one or more afterward, in succession, at about such intervals aswill allowfor the full action of the contents of the previous case; but I believe the better plan to be to have a sufficient number of chambers, and of sucient capacity in each case, so that the desired chemical action in any one charge of molten metal shall be practically accomplished thereby; also, the relative thicknesses of the successive shells, as Well as the relative capacities of the successive chambers formed thereby, may be varied at pleasure, with reference to securing the fusion of the shells and the chemical actions indicated at such stages of the conversion of the metal, as may be preferred, since it is generally believed that the facility or ease with which phosphorus can be eliminated .varies somewhat with the varying temperature and condition of the metal.

If the skilled worker desires to dephosphorize the metal slowly atrst and more rapidly afterward, he willhave his eases made with shells which will fuse more rapidly from the outside toward the inside, or with chambers of greater capacity from the outside toward the inside, and vice versa, or the eii'ect may be varied by varyin g the ingredients in the different chamv bers; or all these variable elements of construction and use may be employed at the same time with reference to getting the best results, as the skilled worker may prefer also, the cases, instead of being cylindrical,' may be made rectangular or of other desired shape, with dividing walls or partitions varying in thickness or relative arrangement, such that the materials contained in the series or nest of chambers so formed will, by the successive fusing of the outer and dividing Walls or partitions, be brought in succession, one after another, into contact or intermixture with the molten metal; and while I have shown a threechamber case, the number of chambers may be varied at pleasure, from two upwardly. For most purposes I believe that three or four will be the best number; and for the elimination of other impurities than phosphorus, the like meansmay be employed, with the mere change ofthe material inclosed in the chambers of the case, which should always be such as adapted to do the work desired under the conditions named.

I claim herein as my inventionl. The method of introducing dephosphorizing or other purifying ingredients in successive measured quantities into a charge of molten metal by inclosing such measured quantities in a series or nest of chambers, the inclosingwalls of which are successively fusible, and introducing such nest directly into the molten charge, substantially as set forth.

2. A close metallic case, A, having one or more inner rings, c2 a3, and iilled in the chambers b b2 with dephosphorizing or other purifying ingredients, substantially as described.

In testimony whereof I have hereunto set my hand.

JOHN WALKER.

Witnesses:

W. R. PALMER, J AMES GIBB. 

